On my Ubuntu I found the timeout is caused by firewall (ufw / iptables).
stevee@Inspiron-1501:/www/vhosts/moodle$ git clone -v git://git.moodle.org/moodle.git
<timeout>
stevee@Inspiron-1501:/www/vhosts/moodle$ sudo ufw disable
Firewall stopped and disabled on system startup
stevee@Inspiron-1501:/www/vhosts/moodle$ git clone -v git://git.moodle.org/moodle.git
Cloning into moodle...
^Cmote: Counting objects: 148096
I have enabled UFW outbound rule for Git (port 9418) and also an inbound rule for SSH from git.moodle.org (174.123.154.58).
sudo ufw allow out 9418/tcp
sudo ufw allow proto tcp from 174.123.154.58 to any port 22
stevee@Inspiron-1501:/www/vhosts/moodle$ sudo ufw status verbose
Status: active
Default: deny (incoming), deny (outgoing)
To Action From
-- ------ ----
Anywhere DENY IN Anywhere
22/tcp ALLOW IN 174.123.154.58
53 ALLOW OUT Anywhere
22,80,443/tcp ALLOW OUT Anywhere
Anywhere DENY OUT Anywhere
9418/tcp ALLOW OUT Anywhere
But this still didn't resolve timeout. I will post again if i figure this out...
by Steve Edwards.